tidb-sql

Original：🇺🇸 English

Translated

1 scripts

Write, review, and adapt SQL for TiDB with correct handling of TiDB-vs-MySQL differences (VECTOR type + vector indexes/functions, full-text search, AUTO_RANDOM, optimistic/pessimistic transactions, foreign keys, views, DDL limitations, and unsupported MySQL features like procedures/triggers/events/GEOMETRY/SPATIAL). Use when generating SQL that must run on TiDB, migrating MySQL SQL to TiDB, or debugging TiDB SQL compatibility errors.

1installs

Sourcepingcap/agent-rules

Added on2026-02-08

NPX Install

npx skill4agent add pingcap/agent-rules tidb-sql

SKILL.md Content

View Translation Comparison →

TiDB SQL (MySQL-compat-focused)

Goal: generate SQL that runs correctly on TiDB by default, and avoid "works on MySQL but breaks on TiDB" constructs.

Workflow (use every time)

Identify the target engine and version:
- Run
```
SELECT VERSION();
```
- If the result contains
```
TiDB
```
  , treat it as TiDB and parse the version (needed for feature gates like Vector / Foreign Key).
- If connecting to TiDB Cloud, ensure the client enables SSL with certificate + identity verification (see
```
skills/tidb-sql/references/tidb-cloud-ssl.md
```
  ).
Ask 2 quick capability questions if the request depends on them:
- "Do you have TiFlash?" (needed for vector indexes)
- "Is this TiDB Cloud Starter/Essential in a supported region for Full-Text Search?" (availability is limited)
Generate SQL using TiDB-safe defaults:
- Avoid unsupported MySQL features (procedures/triggers/events/UDF/GEOMETRY/SPATIAL, etc.)
- Treat views as read-only
- Treat primary key changes as migration/rebuild work
If the user provides MySQL SQL, do a compatibility pass:
- Replace unsupported features with TiDB alternatives
- Call out behavior differences and version prerequisites explicitly
If SQL is slow or fails unexpectedly, use TiDB-native diagnostics:
- Use
```
EXPLAIN FORMAT = "tidb_json"
```
  for structured plans and operator trees.
- Use
```
EXPLAIN ANALYZE
```
  to compare
```
estRows
```
  vs
```
actRows
```
  (it executes the query).
- If the plan looks wrong, consider
```
ANALYZE TABLE ...
```
  to refresh statistics.

High-signal differences (keep in mind)

Vector: TiDB supports
```
VECTOR
```
/
```
VECTOR(D)
```
types and vector functions/indexes; MySQL does not.
No GEOMETRY/SPATIAL: avoid
```
GEOMETRY
```
, spatial functions, and
```
SPATIAL
```
indexes.
No procedures / functions / triggers / events: move logic to the application layer or an external scheduler.
Full-text search (TiDB feature): use TiDB full-text search SQL when available; don't assume MySQL
```
FULLTEXT
```
works everywhere.
Views are read-only: no
```
UPDATE/INSERT/DELETE
```
against views.
Foreign keys: supported in TiDB v6.6.0+; otherwise, don't rely on FK enforcement.
Primary key changes are restricted: assume "create new table + backfill + swap" for PK changes.
AUTO_RANDOM: prefer
```
AUTO_RANDOM
```
over
```
AUTO_INCREMENT
```
for write-hotspot avoidance when appropriate.
Transactions: TiDB supports pessimistic and optimistic modes; handle optimistic
```
COMMIT
```
failures in application logic.

Use these references (inside this skill)

```
skills/tidb-sql/references/vector.md
```
- VECTOR types, functions, vector index DDL, and query patterns.
```
skills/tidb-sql/references/full-text-search.md
```
- Full-text search SQL patterns and availability gotchas.

skills/tidb-sql/references/auto-random.md

-

AUTO_RANDOM

rules, DDL patterns, and restrictions.

```
skills/tidb-sql/references/transactions.md
```
- pessimistic vs optimistic mode and session/global knobs.
```
skills/tidb-sql/references/mysql-compatibility-notes.md
```
- other "MySQL vs TiDB" differences that commonly break SQL.
```
skills/tidb-sql/references/explain.md
```
- EXPLAIN / EXPLAIN ANALYZE usage, tidb_json and dot formats.
```
skills/tidb-sql/references/flashback.md
```
- FLASHBACK TABLE/DATABASE and FLASHBACK CLUSTER recovery playbooks.
```
skills/tidb-sql/references/tidb-cloud-ssl.md
```
- TiDB Cloud SSL verification requirements and client flags.